// This code is derived from jcifs smb client library <jcifs at samba dot org>
// Ported by J. Arturo <webmaster at komodosoft dot net>
//  
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
// 
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
// 
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
namespace SharpCifs.Smb
{
    internal class Trans2QueryFsInformationResponse : SmbComTransactionResponse
    {
        internal const int SMB_INFO_ALLOCATION = 1;

        internal const int SmbQueryFsSizeInfo = unchecked(0x103);

        internal const int SmbFsFullSizeInformation = 1007;

        internal class SmbInfoAllocation : IAllocInfo
        {
            internal long Alloc;

            internal long Free;

            internal int SectPerAlloc;

            internal int BytesPerSect;

            // information levels
            // Also handles SmbQueryFSSizeInfo
            public virtual long GetCapacity()
            {
                return Alloc * SectPerAlloc * BytesPerSect;
            }

            public virtual long GetFree()
            {
                return Free * SectPerAlloc * BytesPerSect;
            }

            public override string ToString()
            {
                return "SmbInfoAllocation[" 
                            + "alloc=" + Alloc 
                            + ",free=" + Free 
                            + ",sectPerAlloc=" + SectPerAlloc 
                            + ",bytesPerSect=" + BytesPerSect + "]";
            }

            internal SmbInfoAllocation(Trans2QueryFsInformationResponse enclosing)
            {
                this._enclosing = enclosing;
            }

            private readonly Trans2QueryFsInformationResponse _enclosing;
        }

        private int _informationLevel;

        internal IAllocInfo Info;

        internal Trans2QueryFsInformationResponse(int informationLevel)
        {
            this._informationLevel = informationLevel;
            Command = SmbComTransaction2;
            SubCommand = Smb.SmbComTransaction.Trans2QueryFsInformation;
        }

        internal override int WriteSetupWireFormat(byte[] dst, int dstIndex)
        {
            return 0;
        }

        internal override int WriteParametersWireFormat(byte[] dst, int dstIndex)
        {
            return 0;
        }

        internal override int WriteDataWireFormat(byte[] dst, int dstIndex)
        {
            return 0;
        }

        internal override int ReadSetupWireFormat(byte[] buffer, int bufferIndex, int len)
        {
            return 0;
        }

        internal override int ReadParametersWireFormat(byte[] buffer, 
                                                       int bufferIndex, 
                                                       int len)
        {
            return 0;
        }

        internal override int ReadDataWireFormat(byte[] buffer, int bufferIndex, int len)
        {
            switch (_informationLevel)
            {
                case SMB_INFO_ALLOCATION:
                    {
                        return ReadSmbInfoAllocationWireFormat(buffer, bufferIndex);
                    }

                case SmbQueryFsSizeInfo:
                    {
                        return ReadSmbQueryFsSizeInfoWireFormat(buffer, bufferIndex);
                    }

                case SmbFsFullSizeInformation:
                    {
                        return ReadFsFullSizeInformationWireFormat(buffer, bufferIndex);
                    }

                default:
                    {
                        return 0;
                    }
            }
        }

        internal virtual int ReadSmbInfoAllocationWireFormat(byte[] buffer, int bufferIndex)
        {
            int start = bufferIndex;
            SmbInfoAllocation info = new SmbInfoAllocation(this);
            bufferIndex += 4;
            // skip idFileSystem
            info.SectPerAlloc = ReadInt4(buffer, bufferIndex);
            bufferIndex += 4;
            info.Alloc = ReadInt4(buffer, bufferIndex);
            bufferIndex += 4;
            info.Free = ReadInt4(buffer, bufferIndex);
            bufferIndex += 4;
            info.BytesPerSect = ReadInt2(buffer, bufferIndex);
            bufferIndex += 4;
            this.Info = info;
            return bufferIndex - start;
        }

        internal virtual int ReadSmbQueryFsSizeInfoWireFormat(byte[] buffer, int bufferIndex)
        {
            int start = bufferIndex;
            SmbInfoAllocation info = new SmbInfoAllocation(this);
            info.Alloc = ReadInt8(buffer, bufferIndex);
            bufferIndex += 8;
            info.Free = ReadInt8(buffer, bufferIndex);
            bufferIndex += 8;
            info.SectPerAlloc = ReadInt4(buffer, bufferIndex);
            bufferIndex += 4;
            info.BytesPerSect = ReadInt4(buffer, bufferIndex);
            bufferIndex += 4;
            this.Info = info;
            return bufferIndex - start;
        }

        internal virtual int ReadFsFullSizeInformationWireFormat(byte[] buffer, 
                                                                 int bufferIndex)
        {
            int start = bufferIndex;
            SmbInfoAllocation info = new SmbInfoAllocation(this);
            // Read total allocation units.
            info.Alloc = ReadInt8(buffer, bufferIndex);
            bufferIndex += 8;
            // read caller available allocation units 
            info.Free = ReadInt8(buffer, bufferIndex);
            bufferIndex += 8;
            // skip actual free units
            bufferIndex += 8;
            info.SectPerAlloc = ReadInt4(buffer, bufferIndex);
            bufferIndex += 4;
            info.BytesPerSect = ReadInt4(buffer, bufferIndex);
            bufferIndex += 4;
            this.Info = info;
            return bufferIndex - start;
        }

        public override string ToString()
        {
            return "Trans2QueryFSInformationResponse[" + base.ToString() + "]";
        }
    }
}
